Naomi Osaka through to US Open third round by Simona Halep crashes out

Naomi Osaka continued her bid for a second straight US Open title with a business-like 6-3 6-4 win over Magda Linette, but No.4 seed Simona Halep is out.

After the match Osaka met one young fan that was overwhelmed by the opportunity to meet her tennis hero, and nucontrollably began crying.

Osaka comforted the girl and gave her an autograph.

Osaka, after struggling with nerves in her gruelling first-round match, was calm and collected as she smacked 13 winners on Louis Armstrong Stadium to dispatch Poland's Linette.

Osaka meets a young fan (ESPN)

After a one-sided first set, trouble brewed for the world No.1 when Linette raced out to a 3-0 lead in the second on a sun-soaked court.

But the 21-year-old Japanese kept her composure and battled back, hitting a deft volley on match point to seal the win before an adoring crowd that included former San Francisco 49er Colin Kaepernick and former Los Angeles Laker Kobe Bryant.

Next up for Osaka is either qualifier Timea Babos or 15-year-old American wildcard Coco Gauff.

Former NBA player Kobe Bryant watches a Women's Singles second round match between Naomi Osaka of Japan Magda Linette (Getty)

Wimbledon champion Halep's disappointing record at Flushing Meadows continued with a defeat by Taylor Townsend in the second round.